BusTools/1553 provides great flexibility and ease in programming Condor Engineering's 1553 products. Sometimes, however, you may want to modify how BusTools/1553 functions. BusTools/1553 runs on top of the BusTools/1553-API. You modify how BusTools/1553 executes by changing the BusTools/1553-API to function the way you need. Although the API source code is provided to allow you to modify the API, it is a hard job. A simpler way to modify how the API executes is through a User-defined DLL interface. This option is described in Chapter 4 of the "BusTools/1553-API Software Reference Manual".
The User DLL Interface allows you to extend and enhance the API, without re-writing the current API or creating your own GUI interface. The standard BusTools/1553 GUI uses this User DLL to extend to function of certain API calls. The list below, shows which functions are available
User DLL Entry Associated API Function ============================================== UsrAPI_Close BusTools_API_Close UsrBC_MessageAlloc BusTools_BC_MessageAlloc UsrBC_MessageWrite BusTools_BC_MessageWrite UsrBC_MessageRead BusTools_BC_MessageRead UsrBC_MessageUpdate BusTools_BC_MessageUpdate UsrBC_StartStop BusTools_BC_StartStop UsrRT_CbufWrite BusTools_RT_CbufWrite UsrRT_MessageRead BusTools_RT_MessageRead UsrRT_StartStop BusTools_RT_StartStop UsrBM_MessageAlloc BusTools_BM_MessageAlloc UsrBM_MessageRead BusTools_BM_MessageRead UsrBM_StartStop BusTools_BM_StartStop
You can write a DLL with some or all of the User DLL entry points above. The code in the DLL can either change of modify how the associated API functions execute.
There is example code showing how to implement the user DLL is Condor Engineering's BusTools/1553-API Source code directory. The two files are named BTUSER0.C and BTUSER1.C. DLLs for these are created with Source files in the BusTools/1553-API Borland Library directory. The DLLs are named BTUSER0.dll and BTUSER1.dll. These User DLL Interfaces can be used with BusTools/1553. You can select one of these DLLs and see how it modifies the operation of BusTools/1553 and the underlying API.
Review Chapter 4 of the "BusTools/1553-API Software Reference Manual" for a complete description of this feature.